As a technique for detecting ultraviolet light with high sensitivity, there is known a technique of converting ultraviolet light into visible light and detecting the visible light with a photodetection element.
Of the converted visible light, obliquely scattered visible light is not incident on the photodetection element, and thus, a photodetection efficiency is lowered.
In addition, the obliquely scattered visible light is incident on adjacent photodetection elements, which causes crosstalk.